Do you think diamonds are jewels?
There are many gemstones on Earth that have been formed over tens of thousands, even hundreds of millions of years. Diamonds are one of those gemstones.
Colored stones have been used for a variety of purposes since ancient times, such as talismans, symbols of power, and women's ornaments. They come in many colors, including red, blue, and green, and are colorful and mysterious. Colored stones never cease to fascinate people.

Index

About the quality of colored stones

colorAbout the quality of the stones

In fact, there are no clear grades for colored stones. For example, while some sapphires are more highly valued in the market for their darker color, there are also customers who prefer sapphires with lighter colors. Colored stones that are highly valued in the market may not necessarily suit your preferences, so we recommend that you see them with your own eyes as much as possible before purchasing.
Generally, stones with a deep, vivid color and few inclusions tend to be valued highly, but this is not always the case. This is where it gets more complex than diamonds!
However, it is good to have some knowledge, so here we will roughly summarize the general evaluations. Please use it as reference.

At Hojudo, we evaluate colored stones based on the following criteria.
In order to help you understand the quality as much as possible even in our online shop, we have posted this item chart on the colored stone loose product page on the Hojudo website, so please check it out as well.

▼Check out loose colored stones

1. Vividness

Vivid colored stones have a glossy shine and sparkle. Personally, I think this is the most important aspect of a colored stone. If the color is not vibrant, the colored stone will end up looking dull. Generally speaking, stones with a strong vividness are preferred.

2. Hue

For example, even within the color blue, there are many different shades, such as blues leaning towards purple or green, and preferences vary. It is often hard to believe that they are the same type of gemstone. It can be difficult to describe in words, so the best thing to do is to see them for yourself.

3. Brightness

There are various types of colored stones, such as aquamarine, which is characterized by its pale blue color, and others, such as ruby, which are preferred for their deep red color. Some customers prefer darker gemstones, while others prefer paler gemstones. However, if a gemstone is too transparent and too pale in color, it will show through when worn as a ring, and the color of your finger will be visible, so you need to be careful when choosing.

4. Inclusions

Inclusions are naturally occurring impurities within a gemstone that are not part of the gemstone itself. They are also well-known as a standard for evaluating diamond clarity. Generally, the fewer inclusions a gem has, the more transparent it is and the higher its value. However, inclusions are also seen as unique features of the gemstone and are beloved by collectors. Many customers bring along photos of inclusions taken under a microscope. Some gemstones, such as star rubies, have fibrous inclusions that form six rays of light, creating an asterism effect, while others, like cat's eye, create a single ray of light resembling a cat's eye (chatoyancy effect), creating a truly artistic effect. This, too, is one of the joys of colored gemstones.

5. Place of origin

The color varies depending on the origin because the composition differs. For example, rubies from Myanmar tend to have a vivid, deep red color known as pigeon blood, while rubies from Thailand tend to be darker and those from Sri Lanka tend to be lighter in color, with Myanmar (Burma) stones trading at the highest prices. We have listed some of the most highly priced colored stones and their origins below for your reference.

Ruby: Myanmar (Burma)
Sapphire: Kashmir, Myanmar (Burma), Sri Lanka
Emerald: Colombia
Paraiba tourmaline: Brazil
Alexandrite: Russia

6. Special designations

Very beautiful colored stones are sometimes given special names. There are famous ones that you may have heard of, as well as rare special names.

Ruby: Pigeon's Blood (bright, deep red)
Sapphire: Royal blue (bright, deep blue) / Cornflower (slightly lighter than royal blue)
Aquamarine: Santa Maria color (bright, deep blue)
Coral: Blood-red coral (bright red coral from Japan)
Garnet: Demantoid (bright pale yellow-green)

7. Untreated (unheated, no oil)

Many colored stones are heat-treated to improve their color. In contrast, unheated colored stones are beautiful without any treatment and are traded at high prices. However, be aware that some colored stones are cloudy simply because they are unheated.
At Houjudo, we recommend choosing the more beautiful looking variety even if it has been heat-treated.
Rubies and sapphires are well-known examples of unheated colored stones, but other colored stones such as aquamarine and Paraiba tourmaline are also commonly heat-treated, so in these cases too, the unheated stones have a higher market value.
Emeralds are naturally rich in inclusions, so they are impregnated with oil to make the inclusions less visible and to make them more durable. Emeralds that are beautiful as they are are sold on the market without being impregnated, and are called non-oil emeralds and are traded at high prices.

+++

There are many types of colored stones, and each has its own unique characteristics, so it's hard to say "this is it!" in one word, but that's what makes choosing one so enjoyable and in depth.
Hojudo has approximately 700 pieces of colored stone jewelry and loose stones on display in the store.
Please feel free to take a look.
If there is a colored stone you are looking for, we can order it for you, so please feel free to contact us.